Other Help Topics :: Java binary locator

I'm planning a bash script for DSL that checks if java binary is located somewhere in the filesystem. If found then make an alias like this: alias java="/opt/javasomething/bin/java" or make a symlink o to $PATH or even better and easier: scrpt itself is in $PATH and if no java is installed it asks if user wants to install java. If yes then it installs java and then executes the original command. Ofcourse if java executable is already found then just run java executable with arguments.

Why this?
Because it is very easy to run java programs in linux only if java is installed. Just as simple as: $ java -jar your_program.jar
And with this script people new to Linux can easily download Java programs and run them in DSL.

I'd like to have some tips about how this script should look for the java executable.
Also opinions about how this script should act are welcome. =)

Look at /usr/local/bin/links for a simple way to do part of it in lua.
This script does not handle files not in PATH, however.

I'm not sure how it would be done in Lua, but something like this might work in Bash:
(untested)

Code Sample

#!/bin/sh
if which java &>/dev/null; then
JAVA=`which java`
elif [ -x "/opt/javasomething/bin/java" ]; then
JAVA="/opt/javasomething/bin/java"
else
echo "retrieving jre1_5_0.uci ..."
mydsl-load jre1_5_0.uci uci && JAVA="/opt/javasomething/bin/java"
fi

if [ -x "${JAVA}" ]; then
exec ${JAVA} "$@"
else
echo "error!"
exit 1
fi

Use this in place of the java command...but don't name it "java" unless it's not in your PATH.

Many thanks. I'll see what I can do.

Don't forget CLASSPATH and some Java stuff wants JAVA_HOME.

I managed to find java binary location like this:

Code Sample

JAVAEXEC=`sudo find /* | grep "/bin/java\$" 2> /dev/null `; echo $JAVAEXEC

At least it works with DSL. =D And that is what I actually need.

Next thing is to add that into script which checks if it is an executable:

Code Sample

if [ -x $JAVAEXEC ]

But I think I should also make it to check if it is a symlink...

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